原文链接及内容

原文链接：https://openlayers.org/en/latest/examples/wms-custom-tilegrid-512x256.html

运行界面

WMS服务可以提供任意大小的切片，此示例在加载服务时，使用了带有非正方形的自定义切片网格。

main.js代码如下：

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import Map from 'ol/Map.js';
import OSM from 'ol/source/OSM.js';
import TileGrid from 'ol/tilegrid/TileGrid.js';
import TileLayer from 'ol/layer/Tile.js';
import TileWMS from 'ol/source/TileWMS.js';
import View from 'ol/View.js';
import {get as getProjection} from 'ol/proj.js';
import {getWidth} from 'ol/extent.js';

const projExtent = getProjection('EPSG:3857').getExtent();
const startResolution = getWidth(projExtent) / 256;
const resolutions = new Array(22);
for (let i = 0, ii = resolutions.length; i < ii; ++i) {
  resolutions[i] = startResolution / Math.pow(2, i);
}
const tileGrid = new TileGrid({
  extent: [-13884991, 2870341, -7455066, 6338219],
  resolutions: resolutions,
  tileSize: [512, 256],
});

const layers = [
  new TileLayer({
    source: new OSM(),
  }),
  new TileLayer({
    source: new TileWMS({
      url: 'https://ahocevar.com/geoserver/wms',
      params: {'LAYERS': 'topp:states', 'TILED': true},
      serverType: 'geoserver',
      tileGrid: tileGrid,
    }),
  }),
];
const map = new Map({
  layers: layers,
  target: 'map',
  view: new View({
    center: [-10997148, 4569099],
    zoom: 4,
  }),
});

界面布局文件index.html代码如下：

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<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8">
    <title>WMS 512x256 Tiles</title>
    <link rel="stylesheet" href="node_modules/ol/ol.css">
    <style>
      .map {
        width: 100%;
        height: 400px;
      }
    </style>
  </head>
  <body>
    <div id="map" class="map"></div>
    <!-- Pointer events polyfill for old browsers, see https://caniuse.com/#feat=pointer -->
    <script src="https://cdn.jsdelivr.net/npm/elm-pep@1.0.6/dist/elm-pep.js"></script>
    <script type="module" src="main.js"></script>
  </body>
</html>